Suction sheet separator apparatus with plural stack capability and suction control

Abstract

Sheet feeding apparatus with an adjustable stack support in confronting relation to a feed opening able to accommodate sheets of various widths, so that one or more stacks of sheets can be supported along the feed opening with the longitudinal center line of any stack being positionable along different selected points along the length of the feed opening. At least about eight selectively controlled suction cups are aligned parallel to the length of the feed opening and encompass most of the opening engaging the bottom surface of the bottom sheet in any stack of sheets and withdraw the sheet from the stack. The spacing between contiguous margins of the suction cups is much less than about two diameters of each cup. The suction cups are preferably supported on the top of a pneumatic tube and are raised with the tube to engage the bottommost sheet in the stack. The pneumatic tube is mounted for pivotal movement upon a rockable carrier framework. A suction control can selectively connect or disconnect suction from any selected suction cup so that suction to the unused cups can be disconected.

What is claimed, is: 
     
       1. Feeding apparatus comprising: adjustable stacking means for supporting the end portion of a stack of sheets in confronting relation to a feed opening having a length encompassing many widths of the narrowest sheet to be accommodated thereby, so that one or more stacks of such material can be supported along said feed opening and the longitudinal center line of any stack thereof can be positioned along different selected points along the length of said feed opening, sheet withdrawal means for engaging the bottom surface of the bottom sheet in any stack of sheets located at almost any position along the length of the feed opening, said sheet withdrawal means comprising suction cups aligned parallel to the length of said feed opening and encompassing most of said length of said feed opening, suction control means for selectively connecting or disconnecting suction from any selected suction cup so that suction to unused cups can be disconnected, carrier means for supporting and moving said suction cups against the end position of the exposed sheet in the stack and then to withdraw the sheet therefrom, said carrier means for the suction cups including a commons support member, said common support member being pivotally supported upon a main carrier means which is raised and lowered to bring the suction cups into and out of engagement with the bottom sheet in said stack, spring means urging said common support member into a fixed position on said main carrier means, and means for simultaneously adjusting the suction plane of each of the suction cups including vertically adjustable abutment means for engaging a portion of said common support member and urging the same against the force of carrier spring means to tilt said support member the desired degree. 
     
     
       2. The feeding apparatus of claim 1 wherein said adjustable abutment means is adjustable to be able to engage a portion of said common support member when it is raised by said main carrier means to a position just below the point where the suction cups will engage the bottom sheet in the stack. 
     
     
       3. Feeding apparatus comprising: adjustable stacking means for supporting the end portion of a stack of sheets in confronting relation to a feed opening having a length encompassing many widths of the narrowest sheet to be accommodated thereby, so that one or more stacks of such material can be supported along said feed opening and the longitudinal center line of any stack thereof can be positioned along different selected points along the length of said feed opening, sheet withdrawal means for engaging the bottom surface of the bottom sheet in any stack of sheets located at almost any position along the length of the feed opening, said sheet withdrawal means comprising a number of suction cups aligned parallel to the length of said feed opening, said suction cups being carried on a horizontally extending pneumatic tube with a longitudinal passageway communicating with a source of low pressure, said pneumatic tube having below each suction cup a vertical sleeve projecting downwardly into said pneumatic tube, the interior of which sleeve communicates with said longitudinal passageway only through one or more openings in said sleeve, suction control means for selectively connecting or disconnecting suction from any selected suction cup so that suction to unused cups can be disconnected, said suction control means comprising a second sleeve mounted for adjustment in said first sleeve between positions which cover and uncover said one or more lateral openings, and means for moving said suction cups toward and away from said feed opening to bring said suction cups against the end position of the exposed sheet in the stack and then to withdraw the sheet therefrom.